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Real-time RT-PCR Ct value is not associated with COVID-19 disease severity: an observational study in tertiary
A Yuwono Soeroto1, R Antartika, N Nauli Asriputri
1Division of Pulmonology and Critical Care Medicine, Department of Internal Medicine, Faculty of Medicine, Universitas Padjadjaran, Hasan Sadikin Hospital, Bandung, Indonesia. aysoeroto@yahoo.co.id.
Insights
The cycle threshold (Ct) value from real-time reverse transcription-polymerase chain reaction (RT-PCR) tests did not significantly correlate with COVID-19 clinical severity in the second week of illness. This finding suggests Ct values have limited clinical significance for assessing COVID-19 severity.
Area of Science:
- Infectious Diseases
- Virology
- Clinical Diagnostics
Background:
- Real-time reverse transcription-polymerase chain reaction (RT-PCR) is the standard diagnostic method for COVID-19.
- The cycle threshold (Ct) value in RT-PCR is often considered an indicator of viral load.
Purpose of the Study:
- To investigate the association between RT-PCR Ct values and the clinical severity of COVID-19.
- To determine if Ct values can predict COVID-19 severity in the second week of illness.
Main Methods:
- A cross-sectional study involving 207 COVID-19 patients.
- Data collected from medical records at a tertiary referral hospital.
- Patients categorized into four severity groups (mild, moderate, severe, critical).
- Statistical analysis using One Way ANOVA Test.
Main Results:
- No statistically significant differences in RT-PCR Ct values were observed across different COVID-19 severity groups.
- Specific p-values for Ct Helicase/ORF1b, Ct RdRp, and lowest Ct genes were all above 0.8.
- These results indicate a lack of correlation between Ct value and disease severity in the second week.
Conclusions:
- While Ct values reflect viral load, they are clinically insignificant for predicting COVID-19 severity in the second week of illness.
- The study highlights the limitations of using Ct values alone for clinical severity assessment in COVID-19 patients.
Objective:
Real-time reverse transcription-polymerase chain reaction (RT-PCR) is the gold standard examination to confirm coronavirus disease 2019 (COVID-19). This study aimed to determine the association between RT-PCR Ct value and COVID-19 clinical severity in the second week of illness.
Patients And Methods:
This study was a cross-sectional study. Data were collected from medical records of COVID-19 patients at the tertiary COVID-19 referral hospital of West Java, Dr. Hasan Sadikin Hospital Bandung, from January to May 2021. A total of 207 patients who met inclusion criteria were divided into four severity groups. The data were analyzed with One Way ANOVA Test.
Results:
There was no significant difference in RT-PCR Ct value among mild, moderate, severe and critical groups measured in the second week of illness, with p=0.825 for Ct Helicase/ORF1b gene, p=0.821 for Ct RdRp gene and p=0.870 for the lowest Ct gene.
Conclusions:
Although Ct value reflects viral load, its role is concluded to be clinically insignificant in terms of association with the severity of COVID-19 in the second week of illness.
